Technical Field
The present invention relates to a method and device for making plant fiber (referred to as plant fiber hereinafter) products including pulps by pressing and molding; for manufacturing plant-fiber molding products (or pulp molding products, hereinafter collectively referred to as plant-fiber molding products), especially for manufacturing non-planar paper products; such as plant fiber tableware, plant fiber trays, industrial plant-fiber shock pads, packaging boxes and trays, non-planar three-dimensional decorative plant-fiber wall panels (or referred to as three-dimensional plant fiber wallpapers or three-dimensional pulp molding wallpapers) and all plant-fiber molding products.
Description of Related Art
The process for making plant-fiber molding products is as follows: plant fibers are made into wet semifinished products by means of a suck-filter forming device after suck-filter forming, which will be alternatively fed into hot-press molds of the left hot press mold solidifying device and the right hot press mold solidifying device on both sides of the suck-filter forming device after being heated to a certain temperature for clamping and hot-press mold drying and solidifying, thus making plant-fiber molding products in various shapes. This is the dual hot press mold solidifying device mode of the method for manufacturing plant-fiber molding products.
The present invention is explained by taking the dual hot press mold solidifying device mode of the method for manufacturing plant-fiber molding products as an example. There is a common three-station full-automatic plant-fiber molding machine, comprising a forming and solidifying top rack, a forming and solidifying low rack, a rod for connecting the forming and solidifying top rack and the forming and solidifying low rack, a suck-filter forming device (forming station) arranged between the forming and solidifying low rack, a left hot press mold solidifying device (or referred to as the left solidifying station) with the left hot-press top and low molds and a right hot press mold solidifying device (or referred to as the right solidifying station) with the right hot-press top and low molds on both sides of the suck-filter forming device, wherein a wet semifinished product transfer device is arranged above the suck-filter forming device and fixed on the forming and solidifying top rack with its transfer mold clamp moveable up and down; furthermore, the left and right hot-press low molds alternatively move below the transfer device respectively along the horizontal track of the hot-press low mold driven by power so as to receive the wet semifinished products transferred from such transfer device. After the wet semifinished products are transferred into the left or right hot-pressure low mold and return just below the left or right hot-pressure top mold from the transfer mold, the left hot-press top mold closes with the left hot-pressure low mold downward and implements the hot press mold solidifying for the wet semifinished products (or the right hot-press top mold closes with the right hot-pressure low mold downward and implements the hot press mold solidifying for the wet semifinished products driven by the external force, such as moving the tank or cylinder from the right hot-press top mold) driven by the external force (moving the tank or cylinder from the left hot-press top mold) until the wet semifinished products are dried and solidified to remove the product by mold opening. Repeat the above steps again and again. This is the full-automatic plant fiber (including pulp) molding machine by means of the dual hot press mold solidifying device mode, consisting of “the left hot press mold solidifying device, suck-filter forming device and the right hot press mold solidifying device”. For example, the plant fiber molding (including pulp molding) machine disclosed in CN patents 03209714.X, ZL201020283075.2, ZL 201010246235.0, ZL201020283085.6 and other related patents are such typical production units.
The wet semifinished products are dried and solidified to remove the products by mold opening in two ways: 1. the full-automatic pulp molding machine is connected with the left and right conveyor belts on the left hot-press low mold (including a mold mounting plate for mounting the left hot-press low mold) and the right hot-press low mold (including a mold mounting plate for mounting the right hot-press low mold). After the wet semifinished products are heated, dried and solidified, the left hot-press top mold opens and absorbs the products to move upward while the left hot-press low mold moves just below the transfer mold, the left conveyor belt is just below the left hot-press top mold as the left hot-press low mold moves to the right and the products absorbed by the left hot-press top mold fall onto the left conveyor belt; afterward, the left conveyor belt also returns to the original position and turns to deliver the products out of the machine with the left hot-press low mold returning to the original position. Similarly, the right hot-press top mold opens and absorbs the products to move upward while the left conveyor belt is just below the right hot-press top mold as the right hot-press low mold moves to the left just below the transfer mold clamp and the products absorbed by the right hot-press top mold fall onto the right conveyor belt; afterward, the right conveyor belt delivers the products out of the machine with the right hot-press low mold returning to the original position. Therefore, the left and right conveyor belts deliver the product out by wet semifinished product forming and hot press mold solidifying. 2. The left and right conveyor belts are replaced with the left plate and the right plate respectively, wherein the products absorbed by the left and right hot-press top molds are blown on the left and right plates respectively. The products are removed from the left and right plates by artificial collection; the left plate with products can be turned to the left at a certain angle so that the products slide out from the left plate or the right plate with products can be turned to the right at a certain angle so that the products slide out from the right plate.
Thus, the dried and solidified products alternatively fall from the left and right hot-pressure top molds and are delivered out from the left conveyor belt (the left plate) or the right conveyor belt (the right plate).
In the prior art, there is a single-side hot press mold solidifying production device arranged on the left or right (either) side of the suck-filter forming device with the same production process as described above. However, one suck-filter forming device is provided with one hot press mold solidifying device, which is known as the single hot press mold solidifying device mode of the method for manufacturing plant-fiber molding products. Moreover, there is a full-automatic plant fiber molding machine with a multi-function auxiliary device to eliminate the mold dripping of the automatic molding machine. Therefore, the process for making plant fiber molding products (including pulp molding products) includes two main processes and functions, namely wet semifinished product forming and hot press mold solidifying in the prior art.
For various reasons, the actual edge of the plant fiber molding products produced by forming and mold solidifying often fails to achieve the design requirements. In order to achieve the precise shape or profile of products, some margin trimming allowances are allowed for the edge of the pre-margin trimmed products and the excess is removed by margin trimming, thus realizing the required process and method by cutting the products into the required shapes. This process and method is known as margin trimming (processes such as removal of extra product edges, product cutting, slitting of single products in integrated products, product punching, product puncturing, cut marks or indentations left on products are all classified as margin trimming).
Until now, all international methods and devices for making and producing plant fiber molding products are designed so that wet semifinished product forming and hot press mold solidifying can be continuously performed on the same device; scattered products cannot be determined in a fixed position after they slide out from the conveyor belt or the left and right plates via hot press mold solidifying. The rim of plant fiber molding products produced has always some rough edges, with which the products are artificially collected and margin trimmed by a margin trimming machine. A method and device cannot be yet achieved to continuously perform the processes below: from wet semifinished product forming to hot press mold solidifying and to scrap removal. As a result, intact, margin trimmed and high-quality products cannot be produced on the same machine.